Loans - TDR's by Class and Specific Reserves (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015 loan	Mar. 31, 2014 loan	Dec. 31, 2014 loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans	90	101	94
Balance	$ 26,524	$ 28,796	$ 27,214
Specific Reserves	695	1,246	868
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans	17	20	19
Balance	11,831	12,925	12,282
Specific Reserves	133	520	267
Commercial construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans	1	1	1
Balance	1,172	1,284	1,172
Specific Reserves	189	277	207
Commercial other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans	13	19	15
Balance	1,789	2,300	2,007
Specific Reserves	0	103	0
Residential term
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans	54	56	54
Balance	10,917	11,450	10,932
Specific Reserves	351	346	373
Home equity line of credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans	5	5	5
Balance	815	837	821
Specific Reserves	$ 22	$ 0	$ 21

Specific allowance for loan and lease losses on receivable financings that are classified as troubled debt restructurings during the period.

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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